Techniques for marking a substrate using a physical vapor deposition material

ABSTRACT

Techniques, processes and structures are disclosed for providing markings on products, such as electronic devices. For example, the markings can be formed using physical vapor deposition (PVD) processes to deposit a layer of material. The markings or labels may be textual and/or graphic. The markings are deposited on a compliant layer that is disposed on a surface to be marked. The compliant layer is arranged to isolate the surface to be marked from the layer of material deposited using the PVD process.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to (i) U.S. Provisional PatentApplication No. 61/236,847, filed Aug. 25, 2009 and entitled “METHOD ANDAPPARATUS FOR APPLYING A PHYSICAL VAPOR DEPOSITION MATERIAL ON ASUBSTRATE,” which is hereby incorporated herein by reference; and (ii)U.S. Provisional Patent Application No. 61/250,369, filed Oct. 9, 2009and entitled “METHOD AND APPARATUS FOR APPLYING A PHYSICAL VAPORDEPOSITION MATERIAL ON A SUBSTRATE,” which is hereby incorporated hereinby reference.

BACKGROUND OF THE INVENTION

1. Field of Invention

The invention relates generally to providing markings on products and,more particularly, to providing markings on substrates using a physicalvapor deposition (PVD) material.

2. Description of the Related Art

Consumer products, e.g., electronic devices, have been marked for manyyears. It is relatively common for electronic devices to be marked orlabeled, for example, with logos, artwork, and information such as aserial number or a model number. Often, substrates associated with anelectronic device may be marked.

Substrates may be marked using a physical vapor deposition (PVD)process. Using a PVD process, a PVD coating formed from a material suchas metal may be deposited directly onto a surface of a substrate to markthe surface of the substrate. The PVD coating is deposited as a layer,e.g., film, that is bonded to the surface of the substrate.

SUMMARY OF THE INVENTION

The invention pertains generally to techniques or processes forproviding markings on products using physical vapor deposition (PVD)processes. By providing a compliant intermediate layer between asubstrate and a layer of PVD material which forms a marking, stresses onthe substrate caused by a PVD process may be substantially reduced.

According to one aspect, a substrate structure can, for example, includea substrate, a compliant layer, and a layer of material deposited on thecompliant layer using a PVD process. The compliant layer can bedeposited on a first surface of the substrate, and can be positionedbetween the substrate and the layer of material deposited using the PVDprocess. The compliant layer can be arranged to isolate the substratefrom the layer of material deposited using the PVD process. In oneembodiment, the substrate is a glass substrate, and the compliant layeris a silicon dioxide layer.

In accordance with another aspect, a portable electronic device can, forexample, include a housing for the portable electronic device, with thehousing including at least a surface to be marked. A buffer layer can bedeposited on the surface to be marked. In addition, to provide one ormore markings to the surface to be marked, a layer of material depositedcan be deposited on the buffer layer such that the buffer layer ispositioned between the substrate and the layer of material deposited.

In accordance with another aspect, a method for forming a substratestructure can, for example, include obtaining a substrate which has atleast a first surface, identifying at least one location to be markedusing a physical vapor deposition PVD material, and depositing anintermediate layer on the substrate at the at least one location.Finally, the method can include depositing a layer of PVD material overthe intermediate layer such that the intermediate layer is sandwichedbetween the substrate and the layer of PVD material. The intermediatelayer can be arranged to isolate the first surface from the layer of PVDmaterial.

In accordance with still another aspect, a method for forming a housingfor an electronic device can, for example, include obtaining a substratehaving at least a first surface, identifying at least one location to bemarked using a deposition, depositing an intermediate layer on thesubstrate at the at least one location, and depositing a layer ofmaterial over the intermediate layer such that the intermediate layer isprovided between the substrate and the layer of material.

In accordance with yet still another aspect, a method for forming ahousing for an electronic device can, for example, include obtaining asubstrate having at least a first surface, identifying at least onelocation to be marked using a deposition, depositing an intermediatelayer on the substrate at the at least one location, and depositing alayer of material over the intermediate layer such that the intermediatelayer is provided between the substrate and the layer of material.

Other aspects and advantages of the invention will become apparent fromthe following detailed description taken in conjunction with theaccompanying drawings which illustrate, by way of example, theprinciples of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be readily understood by the following detaileddescription in conjunction with the accompanying drawings, wherein likereference numerals designate like structural elements, and in which:

FIG. 1A is a diagrammatic side-view cross-sectional representation of asubstrate structure that includes an intermediate or buffer layerbetween a substrate and a layer of physical vapor deposition (PVD)coating or thin film in accordance with a first embodiment.

FIG. 1B is a diagrammatic side-view cross-sectional representation of asubstrate structure that includes an intermediate or buffer layerbetween a substrate and a layer of PVD coating or thin film inaccordance with a second embodiment.

FIG. 2A is a diagrammatic side-view cross-sectional representation of adevice in which substrate structure that includes an intermediate orbuffer layer between a substrate and a PVD coating is incorporated inaccordance with an embodiment.

FIG. 2B is a diagrammatic top-view representation of a device, e.g.,device 220 of FIG. 2A, in which substrate structure that includes anintermediate or buffer layer between a substrate and a PVD coating isincorporated in accordance with an embodiment.

FIG. 3 is a process flow diagram which illustrates a method of forming asubstrate structure that includes using a PVD process in accordance withone embodiment.

FIGS. 4A-4F are cross-sectional views illustrating formation of asubstrate structure according to one embodiment.

FIG. 5 is a flow diagram of a marking process according to oneembodiment.

FIG. 6 is a process flow diagram which illustrates a method of forming asubstrate structure that includes using a PVD process in accordance withanother embodiment.

DETAILED DESCRIPTION OF THE INVENTION

A product, e.g., electronic device, includes a substrate that can bemarked. The substrate may be marked using a physical vapor deposition(PVD) process.

Using a PVD process, a PVD coating formed from a material, such asmetal, may be deposited directly onto a surface of a substrate to markthe surface of the substrate. The PVD coating is deposited as a layer,e.g., film, that is bonded to the surface of the substrate. However, asthe thickness of a layer of PVD coating that is bonded directly onto asurface of a substrate, residual stresses increase within the layer ofPVD coating. Such residual stresses may cause the shape of the layer tochange, thus effectively altering the marking. These residual stressesin a layer of PVD coating may apply contraction or expansion at aninterface between the layer of PVD coating and a surface of a substrate.When the substrate is a relatively brittle, the residual stresses maycause the substrate to crack in the vicinity of the PVD coating. Thatis, local tensile loading may be created on the surface of thesubstrate, thereby compromising the resistance of the substrate tofracture. For example, when a layer of PVD coating is bonded to onesurface of a glass substrate such that a marking is formed, and a forceis applied to an opposite surface of the glass substrate substantiallyover the marking, residual stresses in the layer PVD coating typicallycan cause the glass substrate to crack in a location over the marking.In general, as the thickness of the layer of PVD coating increases, theresistance to the glass substrate to cracking decreases. When asubstrate cracks, the integrity of a device which includes the substratemay be compromised. Thus, there is a need for improved techniques forenabling PVD coating to be used to create markings on surfaces ofsubstrates.

The invention pertains generally to techniques or processes forproviding markings on products. For example, the markings can be formedusing physical vapor deposition (PVD) processes. The markings (e.g.,labeling) may be textual and/or graphic. The markings may be used toprovide a product (e.g., a product's housing) with certain information.The marking may, for example, be use to label the product with variousinformation. When a marking includes text, the text may provideinformation concerning the product (e.g., electronic device). Forexample, the text may include one or more of: name of product, trademarkor copyright information, design location, assembly location, modelnumber, serial number, license number, agency approvals, standardscompliance, electronic codes, memory capacity of device, and the like.When a marking includes a graphic, the graphic may pertain to a logo, acertification mark, standards mark, or an approval mark that is oftenassociated with the product. The marking may be used for advertisementsto be provided on products. The markings may also be used forcustomization (e.g., user customization) of a housing of a product.

A substrate associated with a product may be marked using a materialdeposited using a PVD process. When a PVD coating is deposited directlyon a substrate, residual stresses may be formed in the layer of PVDcoating, thereby decreasing the resistance of the substrate to fracture.To reduce the likelihood of premature fracture in the substrate, e.g.,to substantially prevent significant reduction to a substrate'sresistance to fracture, a complaint intermediate layer (or buffer layer)may be disposed between the surface of the substrate and a layer of PVDcoating (or a thin film of PVD material). Such a complaint intermediatelayer may effectively reduce stresses on the substrate that may becaused by residual stresses in the layer of PVD coating. In general, thecompliant intermediate layer can act as a barrier and thus can isolatethe substrate from the layer of PVD coating.

In one embodiment, a compliant intermediate layer used in a substratestructure may be formed from substantially any material that isrelatively compliant, such that stress from a layer of PVD coating isnot imparted to a substrate. Materials used to form an intermediatelayer may include, but are not limited to including, silicon dioxide(SiO₂), silicon nitride (Si₃N₄), titanium dioxide (TiO₂), fluorinatedanti-smudge coatings, paint, clearcoat, adhesives, and ink. Anintermediate layer may also be formed from any suitable combination ofthese materials. With respect to adhesives, suitable adhesives include aliquefiable optical adhesive, such as a Polyvinyl Acetate (PVA)adhesive. A liquefiable optical adhesive can provide excellenttransparency as well as conformity to surface geometry. One particularexample of a suitable adhesive is ThreeBond TB1630 adhesive from ThreeBond Co., Ltd., Tokyo, Japan.

Referring initially to FIG. 1A, a substrate structure that includes anintermediate (or buffer layer) essentially sandwiched between asubstrate and a layer of PVD coating or thin film will be described inaccordance with a first embodiment. A substrate structure 100 includes asubstrate 104 with surfaces 108 a, 108 b which may be on substantiallyopposite sides of substrate 104. In one embodiment, substrate 104 may bea glass substrate intended for use in a portable electronic device(e.g., a portable computing device or a mobile telephone device). Whensubstrate 104 is a glass substrate intended for use in a device, surface108 a may be arranged to be in an interior of the device and surface 108b may be a user interface surface, e.g., a surface that the user isintended to touch. It should be appreciated that while substrate 104 maybe a glass substrate, substrate 104 may also be formed from othermaterials including, but not limited to including, sapphire, metal,ceramic, and plastic.

An intermediate layer 112 may be deposited, or otherwise substantiallybonded, to surface 108 a of substrate 104. The intermediate layer 112can also be referred to as a barrier layer, a buffer layer or acompliant layer. A layer of PVD material 116 may be deposited onintermediate layer 112. Layer of PVD material 116, or a layer of PVDcoating, may be formed from any suitable metal, as for example chromiumor aluminum. In general, intermediate layer 112 is arranged tosubstantially isolate substrate 104 from layer of PVD material 116.

The overall thicknesses of layer of PVD material 116 and intermediatelayer 112 may vary. As shown in FIG. 1A, within substrate structure 100,layer of PVD material 116 may have a thickness that is greater than orapproximately equal to a thickness of intermediate layer 112.Alternatively, as shown in FIG. 1B, within a substrate structure 100′, alayer of PVD material 116′ may have a thickness that is less than orapproximately equal to a thickness of an intermediate layer 112′.

In general, layer of PVD material 116 may have a thickness of betweenapproximately 25 nanometers (nm) and approximately 200 nm, as forexample approximately 100 nm. The thickness of an intermediate layer mayvary widely, as indicated in FIGS. 1A and 1B. Some intermediate layers,e.g., intermediate layer 112 of FIG. 1A, may be relatively thin relativeto layer of PVD material 116. Other intermediate layers, e.g.,intermediate layer 112′ of FIG. 1B, may be relatively thick relative tolayer of PVD material 116′. The thickness of intermediate layer may bedependent, at least in part, upon the material from which theintermediate layer is formed and the characteristics of the material.For example, if an intermediate layer is formed from materials such asSiO₂, Si₃N₄, TiO2, or a fluorinated anti-smudge coating, theintermediate layer may have a thickness of between approximately 50 nmand approximately 500 nm. When an intermediate layer is formed from amaterial such paint, clearcoat, adhesive or ink, the thickness of theintermediate layer may be between approximately one (1) micrometer (μm)and approximately ten (10) μm.

As mentioned above, a substrate structure which includes an intermediateor buffer layer between a substrate and a layer of PVD coating may beincluded in a device such that the layer of PVD coating is locatedsubstantially inside the device. The device may be a portable electronicdevice such as a personal digital assistant, a digital media player, agame player, a handheld communications device (e.g., mobile phone), orany suitable computing device.

FIG. 2A is a diagrammatic side-view cross-sectional representation of adevice in which substrate structure that includes an intermediate orbuffer layer between a substrate and a PVD coating is incorporated, andFIG. 2B is a diagrammatic top-view representation of the device inaccordance with one embodiment. A device 220 includes a substrate 204that is substantially coupled to a housing 224. Substrate 204 has amarking formed from a layer of PVD coating 216 that is deposited on anintermediate layer 212. Intermediate layer 212 is effectively bonded toa surface of substrate 204 which effectively helps to define an interiorof device 220. As intermediate layer 212 is adhered to the surface ofsubstrate 204 that faces the interior of device 220, both intermediatelayer 212 and layer of PVD coating 216 are substantially inside device220. However, in an alternative embodiment, intermediate layer and PVDcoating can be provided on an outer surface of device 220.

As shown, the marking formed on substrate 204 by layer of PVD coating216 is arranged substantially along the perimeter of substrate 204. Inone implementation, substrate 204 and intermediate layer 212 are highlytranslucent (e.g., clear) such that when device 220 is viewed from theoutside, PVD coating 216 appears as if it is directly on substrate 204.It should be appreciated, however, that the size, shape and position ofthe marking may vary widely. Further, the number of markings may alsovary widely.

With reference to FIG. 3, a process of forming a substrate structurethat will be described in accordance with one embodiment. A process 301of forming a substrate structure includes obtaining a substrate in step305. As previously mentioned, the substrate may be formed from anysuitable material including, but not limited to including, glass,sapphire, metal, ceramic, and plastic. Once the substrate is obtained,the appropriate surface, e.g., the surface of the substrate onto whichan intermediate layer is to be deposited, may be prepared in an optionalstep 309. Preparing the appropriate surface may include cleaning thesurface and/or masking the surface. As will be appreciated by thoseskilled in the art, masking the surface may allow an intermediate layerto subsequently be deposited in appropriate locations on the surface ofthe substrate. In other words, masking the surface may facilitateidentifying at least one location that is subsequently to be effectivelymarked using a PVD material.

In step 313, an intermediate layer is deposited on the appropriatesurface of the substrate. The intermediate layer may be deposited usingany suitable method. The intermediate layer may be formed from materialsincluding, but not limited to including, SiO₂, Si₃N₄, TiO₂, fluorinatedanti-smudge coatings, paint, clearcoat, adhesive, and ink. Depositingthe intermediate layer may involve monitoring a thickness of theintermediate layer to ascertain when a desired thickness of theintermediate layer is reached.

From step 313, process flow proceeds to step 317 in which a PVD processis used to deposit PVD material onto the intermediate layer. Depositingthe PVD material onto the intermediate layer allows a layer of PVDcoating, or thin film, to be formed on the intermediate layer. The PVDmaterial may be a metal such as chromium, aluminum, or silver. It shouldbe appreciated, however, that the PVD material is not limited to beingchromium, aluminum, or silver. The PVD process may include monitoring athickness of a layer of PVD coating to determine when the layer of PVDcoating reaches a desired thickness. It should be appreciated that if amask is used to effectively control where an intermediate layer and alayer of PVD coating are formed, the mask may be removed when the layerof PVD coating reaches a desired thickness.

After the layer of PVD coating is deposited, a substrate structure whichincludes the substrate, the intermediate layer, and the layer of PVDcoating is effectively formed, and the process of creating a substratestructure is effectively completed. As will be understood by thoseskilled in the art, however, creating a substrate structure may includeoptionally assembling the substrate structure into a device, e.g., aportable electronic device, in step 321.

FIGS. 4A-4F are cross-sectional views illustrating formation of asubstrate structure according to one embodiment. FIG. 4A illustrates asubstrate 400 on which marking is to be eventually provided. As notedabove, the substrate can be formed of various different materials.However, in one implementation, substrate 400 is formed of a translucentmaterial such as glass or sapphire. FIG. 4B illustrates a bufferinglayer 402 provided on an exposed surface 401 of substrate 400. Bufferinglayer 402 is adhered to exposed surface 401 of substrate 400. As notedabove, buffering layer 402 can be a material including, but not limitedto including, SiO₂, Si₃N₄, TiO₂, fluorinated anti-smudge coatings,paint, clearcoat, adhesive, and ink. In the case of adhesive, suitableadhesives include a liquefiable optical adhesive, such as a PolyvinylAcetate (PVA) adhesive. A liquefiable optical adhesive can provideexcellent transparency as well as conformity to surface geometry. Oneparticular example of a suitable adhesive is ThreeBond TB1630 adhesivefrom Three Bond Co., Ltd., Tokyo, Japan. Buffering layer 402, onceapplied to substrate 400, may have a release liner and make further needto cure. Although not shown, if a release liner is present, the releaseliner would be removed. Regardless of whether buffering layer uses arelease liner, an exposed surface 403 of buffering layer 402 tends to beirregular which tends to reduce quality of any marking subsequentlyplaced on buffering layer 402.

FIG. 4C illustrates a compression member 404 that is to be forcedagainst buffering layer 402 provided on substrate 400. The compressionmember 404 is applied against buffering layer 402 using a force so thatbuffering layer 402 is placed under pressure (P). Heating is alsoprovided to soften or liquefy buffer layer 402. The temperature (T) forthe heating varies with the nature of the buffering layer 402. Forexample, the temperature (T) can be 80 degrees Celsius in oneimplementation. The heating can be provided by compression member 404 orby separate means. Compression member 404 is a planar surface and can beform of various materials. For example, compression member can be formedof glass or metal. The compression member 404 can be coated withmaterial (e.g., non-stick coating, such as Teflon) to reduce itsadhesion to buffering layer 402. FIG. 4D illustrates compression member404 forced against buffering layer 402. Due to pressure and/ortemperature imposed, buffering layer 402 conforms to a uniformly smoothexposed surface 403′ resulting in a uniform buffering layer 402′. Toinduce or accelerate curing, ultraviolet (UV) light 406 can be directedtowards buffering layer 402′. In one implementation, if compressionmember 404 is transparent, UV light 406 can be directed towardsbuffering layer 403 through compression member 404. FIG. 4E illustratesthe substrate structure after compression member 404 has been removed.Buffering layer 402′ now has exposed surface 403′ that is uniformlysmooth.

FIG. 4F illustrates a marking layer 408 provided on buffering layer402′. Marking layer 408 can be provided on buffering layer 402′ by a PVDprocess. Depositing PVD material onto buffering layer 402′ allows alayer of PVD coating, or thin film, to be formed on buffering layer402′. The PVD material may be a metal such as chromium, aluminum, orsilver. The markings may be textual and/or graphic. The markings may beused to provide a product (e.g., a product's housing) with certaininformation. The marking may, for example, be use to label the productwith various information. Although cross-sectional view in FIG. 4Fillustrates the marking layer 408 extending across the buffering layer402′, the marking layer 408 need not extend over the entirety of thebuffering layer 402′.

FIG. 5 is a flow diagram of a marking process 500 according to oneembodiment. The marking process 500 operates to mark (or label) anelectronic device, such as a portable electronic device. The marking canbe precise, high resolution and uniform. The marking process 500 caninitially obtain a substrate at step 502. An intermediate layer can thenbe deposited on an appropriate surface of the substrate in step 504. Thesubstrate can pertain to a portion of a housing for an electronic deviceor can pertain to a structure that is otherwise an outer surface for theelectronic device. As one example, the substrate can pertain to a touchscreen surface, such as a touch screen surface formed of glass. Theintermediate layer can be adhered to appropriate surface of thesubstrate. For example, the intermediate layer can be bonded to theappropriate surface of the substrate. Next, at step 506, theintermediate layer can be compressed towards the appropriate surface ofthe substrate to render the exposed surface of the intermediate layeruniform and flat. The intermediate layer may also be heated. Theintermediate layer under press and heated can soften or liquefy so as toconform to surface geometry and provide a flat exposed surface.Thereafter, the exposed surface of the intermediate layer can havemarking material deposited thereon. In one embodiment, the markingmaterial involves deposition of a PVD material using a PVD process. Thedeposited marking material serves to mark (or label) the substrate of anelectronic device.

With reference to FIG. 6, a process of forming a substrate structurethat will be described in accordance with one embodiment. A process 600of forming a substrate structure includes obtaining a substrate in step602. As previously mentioned, the substrate may be formed from anysuitable material including, but not limited to including, glass,sapphire, metal, ceramic, and plastic. Once the substrate is obtained,the appropriate surface, e.g., the surface of the substrate onto whichan intermediate layer is to be deposited, may be prepared in an optionalstep 604. Preparing the appropriate surface may include cleaning thesurface and/or masking the surface. As will be appreciated by thoseskilled in the art, masking the surface may allow an intermediate layerto subsequently be deposited in appropriate locations on the surface ofthe substrate. In other words, masking the surface may facilitateidentifying at least one location that is subsequently to be effectivelymarked using a PVD material.

In step 606, an intermediate layer is deposited on the appropriatesurface of the substrate. The intermediate layer may be deposited usingany suitable method. The intermediate layer may be formed from materialsincluding, but not limited to including, SiO₂, Si₃N₄, TiO₂, fluorinatedanti-smudge coatings, paint, clearcoat, adhesive, and ink. Depositingthe intermediate layer may involve monitoring a thickness of theintermediate layer to ascertain when a desired thickness of theintermediate layer is reached.

In step 608, the intermediate layer is compressed using a compressionsurface. For example, the intermediate layer can be an adhesive thatunder pressure and elevated temperature softens or liquefies so as toconform to and bond with the substrate and also to provide a smooth,uniform, flat exposed surface. The intermediate layer, e.g., adhesive,can then be cured at step 610. For example, UV light can be directedtowards the intermediate layer to accelerate or activate curing.

From step 610, process flow proceeds to step 612 in which a PVD processis used to deposit PVD material onto appropriate portions theintermediate layer. Depositing the PVD material onto the intermediatelayer allows a layer of PVD coating, or thin film, to be formed on theintermediate layer. The PVD material may be a metal such as chromium,aluminum, or silver. It should be appreciated, however, that the PVDmaterial is not limited to being chromium, aluminum, or silver. The PVDprocess may include monitoring a thickness of a layer of PVD coating todetermine when the layer of PVD coating reaches a desired thickness. Itshould be appreciated that if a mask is used to effectively controlwhere an intermediate layer and a layer of PVD coating are formed, themask may be removed when the layer of PVD coating reaches a desiredthickness.

After the layer of PVD coating is deposited, a substrate structure whichincludes the substrate, the intermediate layer, and the layer of PVDcoating is effectively formed, and the process of creating a substratestructure is effectively completed. As will be understood by thoseskilled in the art, however, creating a substrate structure may includeoptionally assembling the substrate structure into a device, e.g., aportable electronic device, in step 614.

Although only a few embodiments of the invention have been described, itshould be understood that the invention may be embodied in many otherspecific forms without departing from the spirit or the scope of thepresent invention. By way of example, while an intermediate layer and alayer of PVD coating have been described as being deposited on a side ofa substrate that is to be substantially inside of a device, it should beappreciated that an intermediate layer and a layer PVD coating mayinstead be deposited on a side of the substrate that is to besubstantially outside of the device.

The use of an intermediate layer as a buffer between a substrate and alayer of PVD coating is particularly suitable for reducing theoccurrence of premature fractures in brittle substrates, e.g.,substrates which are formed from glass. However, an intermediate layerin a substrate structure may be used to reduce stresses on any suitablesubstrate, including those which are not substantially brittle.

In general, an intermediate layer may include discrete portionsconfigured to correspond to a marking that is to be formed by a PVDcoating. That is, an intermediate layer may have substantially the samefootprint as a marking that is formed by the PVD coating. Theintermediate layer, however, is not limited to having substantially thesame footprint as a marking. For instance, the intermediate layer mayinstead be arranged to cover substantially all of a surface of asubstrate, while the marking covers only certain portions of theintermediate layer and, hence, the substrate. In other words, anintermediate layer may be substantially continuous, rather thandiscrete. Portions of the intermediate layer which are not overlaid by aPVD coating may, in some instances, be arranged to enhance the overallcosmetic appearance of the substrate.

As mentioned above, an intermediate layer may include a plurality ofsub-layers. In other words, an intermediate layer may be formed fromsub-layers of different materials, and is not limited to being formed asa substantially single layer using a single material.

The thicknesses of an intermediate layer and a layer of PVD coating mayvary widely depending upon factors which may include, but are notlimited to including, the thickness of a substrate, the size of amarking to be provided on the substrate, and the materials used to formthe intermediate layer and/or the layer PVD coating.

U.S. Provisional Patent Application No. 61/236,847, filed Aug. 25, 2009and entitled “Method and Apparatus for Applying a Physical VaporDeposition Material on a Substrate” is hereby incorporated herein byreference.

Numerous specific details are set forth in order to provide a thoroughunderstanding of the invention. However, it will become obvious to thoseskilled in the art that the invention may be practiced without thesespecific details. The description and representation herein are thecommon meanings used by those experienced or skilled in the art to mosteffectively convey the substance of their work to others skilled in theart. In other instances, well-known methods, procedures, components, andcircuitry have not been described in detail to avoid unnecessarilyobscuring aspects of the invention.

In the foregoing description, reference to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment can beincluded in at least one embodiment of the invention. The appearances ofthe phrase “in one embodiment” in various places in the specificationare not necessarily all referring to the same embodiment, nor areseparate or alternative embodiments mutually exclusive of otherembodiments. Further, the order of blocks in process flowcharts ordiagrams representing one or more embodiments of the invention do notinherently indicate any particular order nor imply any limitations inthe invention.

The many features and advantages of the invention are apparent from thewritten description. Further, since numerous modifications and changeswill readily occur to those skilled in the art, the invention should notbe limited to the exact construction and operation as illustrated anddescribed. Hence, all suitable modifications and equivalents may beresorted to as falling within the scope of the invention.

What is claimed is:
 1. A portable electronic device, comprising: a housing for the portable electronic device, the housing including at least a surface to be marked; a buffer layer deposited on the surface to be marked; and a layer of material deposited, the layer of material deposited being deposited on the buffer layer such that the buffer layer is positioned between the surface and the layer of material deposited, wherein the layer of material serves to provide one or more markings to the surface to be marked, wherein the buffer layer is arranged to reduce stress on the surface to be marked that would otherwise be induced by the layer of material if provided directly on the surface to be marked, wherein the buffer layer has a thickness of between approximately 50 nm and approximately 500 nm.
 2. The portable electronic device of claim 1 wherein the buffer layer is an adhesive layer.
 3. The portable electronic device of claim 2 wherein the adhesive is a liquefiable optical adhesive.
 4. The portable electronic device of claim 2 wherein the adhesive is Polyvinyl Acetate (PVA) adhesive.
 5. The portable electronic device of claim 2 wherein the layer of material to be deposited comprises metal.
 6. The portable electronic device of claim 2 wherein the layer of material is deposited using a physical vapor deposition (PVD) process.
 7. The portable electronic device of claim 2 wherein the surface to be marked is translucent.
 8. The portable electronic device of claim 1 wherein the surface to be marked is glass.
 9. The portable electronic device of claim 1, wherein the layer of material to be deposited comprises metal, wherein the layer of material is deposited using a physical vapor deposition (PVD) process, and wherein the surface to be marked is glass.
 10. The portable electronic device of claim 9 wherein the buffer layer comprises an adhesive layer.
 11. The portable electronic device of claim 9 wherein the buffer layer is compressed before the layer of material is deposited on the buffer layer.
 12. The portable electronic device of claim 1 wherein the layer of material is deposited using a physical vapor deposition (PVD) process, and wherein the buffer layer is arranged to isolate the surface to be marked from the layer of material deposited using the PVD process.
 13. The portable electronic device of claim 1 wherein the surface to be marked is selected from a group including a glass, a metal, a ceramic, and a plastic.
 14. The portable electronic device of claim 1 wherein the layer of material deposited is a metal layer, the metal layer having a thickness of between approximately 25 nanometers (nm) and approximately 200 nm.
 15. The portable electronic device of claim 14 wherein the buffer layer is formed from at least one selected from a group including silicon dioxide, silicon nitride, titanium dioxide, and a fluorinated anti-smudge coating.
 16. The portable electronic device of claim 1 wherein the buffer layer is compressed before the layer of material is deposited on the buffer layer.
 17. The portable electronic device of claim 1 wherein the buffer layer is formed from at least one selected from a group including paint, clearcoat, and ink.
 18. The portable electronic device of claim 1 wherein the buffer layer has a thickness of between approximately 1 micrometer (μm) and approximately 10 micrometers (μm).
 19. The portable electronic device of claim 1 wherein the surface to be marked is in the interior of the housing, and wherein the buffer layer and the layer of material are located in the interior of the housing.
 20. A portable electronic device, comprising: a housing for the portable electronic device, the housing including at least a surface to be marked; a buffer layer deposited on the surface to be marked; and a layer of material deposited, the layer of material deposited being deposited on the buffer layer such that the buffer layer is positioned between the surface and the layer of material deposited, wherein the layer of material serves to provide one or more markings to the surface to be marked, wherein the buffer layer is arranged to reduce stress on the surface to be marked that would otherwise be induced by the layer of material if provided directly on the surface to be marked, wherein the layer of material to be deposited comprises metal, wherein the layer of material is deposited using a physical vapor deposition (PVD) process, wherein the surface to be marked is glass, and wherein the surface to be marked is in the interior of the housing, and wherein the buffer layer and the layer of material deposited using the PVD process are located in the interior of the housing.
 21. The portable electronic device of claim 20 wherein the buffer layer has a thickness of between approximately 50 nm and approximately 500 nm.
 22. The portable electronic device of claim 20 wherein the buffer layer is formed from at least one selected from a group including paint, clearcoat, and ink.
 23. The portable electronic device of claim 20 wherein the buffer layer has a thickness of between approximately 1 micrometer (μm) and approximately 10 micrometers (μm).
 24. A portable electronic device, comprising: a housing for the portable electronic device, the housing including at least a surface to be marked; a buffer layer deposited on the surface to be marked; and a layer of material deposited, the layer of material deposited being deposited on the buffer layer such that the buffer layer is positioned between the surface and the layer of material deposited, wherein the layer of material serves to provide one or more markings to the surface to be marked, wherein the layer of material is deposited using a physical vapor deposition (PVD) process, wherein the layer of material to be deposited comprises metal, wherein the surface to be marked is glass, wherein the surface to be marked is in the interior of the housing, and wherein the buffer layer and the layer of material are located in the interior of the housing.
 25. The portable electronic device of claim 24 wherein the buffer layer has a thickness of between approximately 50 nm and approximately 500 nm.
 26. The portable electronic device of claim 24 wherein the buffer layer is compressed before the layer of material is deposited on the buffer layer. 